A little grow log from Hawaii. Here in Hawaii, i use the crappiest of top soils, 15 gallons in a wheelbarrow and i amend it with 5 gallons of horse crap that is about 3 months old, 4 gallons of black cinders, 2.5 gallons vermiculate, 2 gallons of 100% worm castings, 2 cups blood meal, 2 cups bone meal and mix well. I only use organic nutes, primarily fish emulsions in veg and flower with black strap molasses and a fungi innoculant. The ladies are about 9' tall and the trunks are the size of a red bull can in 5 gallon pails. I have only topped them one or twice, but with my next grows I wanna start mainlining things to keep the height more manageable.